Introduction to Machine Learning with Python and Scikit-Learn

I deal with machine learning and web graphs analysis (mostly in theory). I also work on the development of Big Data products for one of the mobile operators in Russia. It's the first time I write a post, so please, don't judge me too harshly. Nowadays, a lot of people want to develop efficient algorithms and take part in machine learning competitions. So they come to me and ask: "Where to start?".